The disease called rapid ohia death has hit hundreds of thousands of ohia lehua trees on the Big Island. As of last year, it was found to have affected 50 per cent of the ohia trees across 6,000 acres of forest, but it’s believed to have spread further since then. To date, it’s been found primarily in Puna but also in Kona and Kau. It hasn’t been seen anywhere else in the world.

Robert Hauff, the forest health co-ordinator at the state Department of Land and Natural Resources, said the state is planning aerial surveys next month to learn how many acres are affected by the fungus. A world expert in similar diseases is also expected to visit the islands to advise the state on how to control the outbreak.

“Worst case scenario is that it spreads statewide and it decimates all of our ohia forests. It’s a pretty bleak picture,” Hauff told reporters at a news conference in Honolulu.

Ohia is important to the water supply because it’s so effective at soaking water into the ground and replenishing the watershed. It’s critical for native birds because the animals feed on its nectar. It provides a canopy to native plants growing underneath it in the forests.

The state Department of Agriculture has created rules prohibiting moving wood, flowers and other parts of the ohia tree between islands. The state is also encouraging people to clean tools used on ohia and clean shoes and clothes used near ohia.

Christy Martin, a spokeswoman for the Hawaii Coordinating Group on Alien Pest Species, said the fungus is “sneaky” because it can infect a tree for months before showing any symptoms.

“So somebody could think they’re walking through a healthy forest, picking up wood and doing whatever they’re doing collecting for lei and not know they’re dealing with an infected tree,” Martin said after the news conference.

Sam Ohu Gon III, senior scientist and cultural adviser at the Nature Conservancy of Hawaii, said ohia wood was used for weapons, hula instruments, homes and temples in ancient Hawaii. Many Hawaiian proverbs and sayings reference the tree.

“It’s a fundamental blow to the natural foundations of Hawaiian culture as far as I’m concerned,” Gon said. “It’s very important thing, therefore, for anyone who has any love at all for those elements of where we live.”